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 Purpose: Computes the quantum flux.
          See review Eqs.(197-201) for a definition of the output

Usage : flux [-f -i -o -ed -dvr -t -n -lo -hi -p -P -O -e -x -d -v -w -r -c -exp -u 
        -sm -es -wtt -nofs -noev -DB -ver -h -?] [emin emax unit CAP-dof CAP-type] [.inp-file].

Options : 
 -f FILE : The wavefunction is read from file FILE rather than from ./psi
           The string FILE may be a relative or a full path-name.
 -i FILE : The operator is read from file FILE rather than from ./oper
           The string FILE may be a relative or a full path-name.
 -dvr FL : The DVR information is read from file FL rather than from ./dvr
           The string FL may be a relative or a full path-name.
 -ed FL  : The energy distribution is read from file FL rather than from ./enerd
           The string FL may be a relative or a full path-name.
           One may use a flux-file as energy-distribution file.
           In this case, the flux-column will be taken as edstr.
           If a "d" follows the file-name, the DELTA(E) column will be taken.
           If a "+" follows the file-name, the present flux will 
           be added to the edstr input.
           Alternatively, one may use a spectrum.pl (autospec)
           or a cspec.pl (crosspec) file as energy distribution.
           The options "d" and "+" work here as well. With "d" 
           the third (rather than the second) column of the ed-file
           is used, and with "+" the data is added to DELTA(E)
           rather than overwriting it.
 -o PATH : The output is directed to PATH rather than to the current directory.
           The string PATH may be a relative or a full path-name.
           If PATH=no, i.e. "-o no", no output-files will be opened.
 -n step : Compute Wtt' only every step-th psi-output.
 -es nst : Compute the flux for the electronic state nst only.
 -lo klo : Compute Wtt' only from the klo-th psi-output onwards.
 -hi khi : Compute Wtt' only up to the khi-th psi-output.
 -p I    : The no. of energy-points is I rather than  500.
 -e R U  : The offset energy is set to R in units U; e.g. "-e 0.3 ev". 
           Note: "-e lsth" is equivalent to "-e 4.74746 ev".
           Give here the negative of "Energy shift (E_total - E_kinetic)",
           which was printed to log-file. (correction=dia).
 -s strt : Set the starting point of the flux evaluation to strt.
           Default is the grid-point where the cap starts.
 -t      : Test run.  Check of the data sets. No output files opened.
 -P      : Use projectors. -P is followed by the mode number, the projector
           name and up to 8 parameters. The input is closed by a "%".
           There may be several projectors. Example:
           -P 3 KLeg 2 1 % -P 2 eigenf vib 6 %
 -O oper : Apply operator "oper" before measuring the flux.
 -u unit : Transform flux to unit "unit".
           (useful when a operator is applied).
           Note: Rather than a unit one may give a number.
 -w      : The gtau file may be overwritten. Without -w option
           gtau is read from the gtau file (if it exist).
 -r      : Enforce reading the gtau file. Stop if gtau does not exist.
 -v      : Re-compute only the theta part of gtau.
           (useful in combination with the -s option).
 -x      : Evaluate flux only for the theta part of gtau.
           (useful for tests in combination with the -s -v options).
 -d      : Compute gtau from spatial derivative of wavefunction.
 -c icos : Cosine**icos damping of gtau.
 -exp n tau: exp(-(t/tau)**n) damping of gtau
 -sm     : smooth Delta(E) by averaging the enerd data over 5 points.
 -Mb norm: Flux spectrum in Mb. norm is ||D*Psi|| (in au)
           where D is the Dipole moment.
 -wtt    : Only wtt and iwtt are computed.
           Note: The arguments
 "Emin, Emax, unit" must not be given when -wtt is set.

 -nofs   : No transformation to fs.
           Use when "time-not-fs" was set in mctdh.
 -noev   : No transformation to eV.
           Use when "energy-not-ev" was set in mctdh.
 -DB PATH : The path to a direct dynamics DB.
 -ver    : Version information about the program 
 -h      : Print this help text. 
 -?      : Print this help text. 

 The arguments specify the energy interval and
 the degree of freedom of the CAP.
 The CAP-dof may be a number or a modelabel.
 The CAP-type may "right", "left" or "both". "right" is the default.
 If the number given as CAP-dof is larger than the number of DoFs,
 this number is interpreted as the H-term, h, of the CAP.
 Example: flux -lo 25 -w 0.3 2.5 ev rd
          flux 1000 3000 cm-1  x left
          flux -wtt -s 21  y
 If no argument is given, the user is prompted for the missing argument(s).
 The path of an input file may be given as the very last argument.
 Options will overwrite the input-file.
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